Re: [Qemu-devel] [TestDays] s390x emulation error

[Alexander Graf <agraf@suse.de>]

On 11/14/2011 06:29 PM, Andreas Färber wrote:
> Am 10.11.2011 13:36, schrieb Alexander Graf:
>> On 10.11.2011, at 12:29, Andreas Färber<afaerber@suse.de>  wrote:
>>
>>> Am 10.11.2011 11:32, schrieb Alexander Graf:
>>>> On 10.11.2011, at 10:53, Andreas Färber<afaerber@suse.de>  wrote:
>>>>
>>>>> Is there a known issue with running multiple instances of
>>>>> qemu-system-s390x? I got a hang on openSUSE 12.1 RC2 x86_64 host:
>>>>>
>>>>> 0x00007f0de7f698d4 in __lll_lock_wait () from /lib64/libpthread.so.0
>>>>> (gdb) bt
>>>>> #0  0x00007f0de7f698d4 in __lll_lock_wait () from /lib64/libpthread.so.0
>>>>> #1  0x00007f0de7f651c5 in _L_lock_883 () from /lib64/libpthread.so.0
>>>>> #2  0x00007f0de7f6501a in pthread_mutex_lock () from /lib64/libpthread.so.0
>>>>> #3  0x000000000048b4a9 in qemu_mutex_lock (mutex=<optimized out>)
>>>>>    at /home/andreas/QEMU/qemu/qemu-thread-posix.c:54
>>>>> #4  0x00000000004cd3df in qemu_mutex_lock_iothread ()
>>>>>    at /home/andreas/QEMU/qemu/cpus.c:843
>>>>> #5  0x0000000000467580 in main_loop_wait (nonblocking=<optimized out>)
>>>>>    at /home/andreas/QEMU/qemu/main-loop.c:459
>>>>> #6  0x0000000000408984 in main_loop () at /home/andreas/QEMU/qemu/vl.c:1481
>>>>> #7  main (argc=<optimized out>, argv=<optimized out>, envp=<optimized out>)
>>>>>    at /home/andreas/QEMU/qemu/vl.c:3474
>>>>>
>>>>> Key presses didn't work, SDL window doesn't close, at 99.9% CPU.
>>>> Huh? This is all generic code O_o. And no, it's not a known issue.
>>> Hm, reproducable by running
>>>
>>> $ s390x-softmmu/qemu-system-s390x
>>>
>>> (without arguments) on s390-next branch.
>>>
>>> I get compat_monitor0 console, but monitor or switching to real console
>>> don't work and neither does closing. Same backtrace.
>>>
>>> Doesn't happen with ppc-softmmu/qemu-system-ppc or x86_64. Maybe an
>>> issue with the monitor, only apparent when then monitor is shown at
>>> startup rather than later user-invoked? Any suggestions?
>> Maybe the guest is executing an endless loop? Could you try to compile this asm blob for ppc and execute it with -kernel?
>>
>> Test.S:
>>
>> _start:
>>    b .
>>
>>
>> Compile with gcc test.S -nostdlib
> Nope, doesn't hang.

Hrm. Paolo, any idea?


Alex